助剂在农药中的应用

农药助剂是化学农药加工剂型中除中有效成分之外所使用的各种辅助剂的总称。助剂本身没有生物活性，但在剂型配方中或施药中是不可缺少的添加物，添加助剂的主要目的是提高药效、降低农药的用量、节约成本、减少农药对环境的污染。助剂对农药尤其是除草剂的增效作用主要是通过增加农药在植物表面的滞留量、延长滞留时间和提高对植物表皮的穿透能力。因助剂的种类不同，其作用机理也不一样。在使用中，以乳化剂、润展剂等表现活性剂为多，用途较广，对药剂性能影响也较大。     

2003年我国农药械市场概况与2004年农药械市场需求分析与展望

2003年的农药市场基本平稳、结构继续发生变化，一些质优价廉、低残留、药效好的新型杀虫剂、杀菌剂、除草剂以及混配制剂销售明显上升；高毒、高残留农药需求明显回落，市场份额减缩；常规农药品种出现供过于求，农民已完全掌握了市场主动权，随用随买，给旺季供应带来了压     

日本植保无人飞机施用农药制剂登记管理情况分析

日本对植保无人飞机施用农药实行登记管理制度,并及时发布无人飞机用登记农药制剂产品相关情况。截至2020年11月,日本登记用于植保无人飞机的农药制剂产品达到了316个,包括有杀虫剂、杀菌剂、除草剂和植物生长调节剂,登记剂型有乳油、微乳剂、水乳剂、水剂、颗粒剂等,其中登记的除草剂制剂多为颗粒剂。对于乳油、水乳剂、微乳剂、水分散粒剂等对水稀释喷雾的农药制剂,日本通常采用增加施药方法的登记方式,即该产品已经获得了地面常规喷雾的登记前提下,提出增加施药方法——无人飞机低容量喷雾方式施药;对于颗粒剂、超低容量制剂等无需对水稀释的农药制剂,登记申请者可以直接申请植保无人飞机施药。对于植保无人飞机专用制剂的农药登记试验,除了药效、作物安全性等登记试验之外,还需要开展雾滴沉积分布检测。获得登记的植保无人飞机专用农药制剂,需要在农药标签中明确标注其使用信息,包括登记作物、施药剂量、喷液量或颗粒撒施量,无人飞机的飞行高度、天气条件限定及飘移风险控制等。     

国内外农药剂型进展及其发展设想

(一)农药剂型的发展开发出一个好的制剂可以提高药效、降低毒性、节约成本、扩大老品种的应用范围、延长现有药剂的寿命、开拓产品的销路和增强市场的竞争能力。农药新剂型的研制是针对原有剂型所存在的问题经改进而发展起来的。现在让我们看一下现有剂型存在的问题和改进方法,以及应发展的新剂型(见表1)。     

国内农药剂型加工行业的现状及展望

农药剂型加工是农药商品化生产和应用推广的前提,也是农药学研究的重要方向。未来人口的持续增长对粮食生产的需求量也不断增大,而通过传统剂型改良和新剂型研制是实现作物化学保护比较迅速有效的途径。本文从环保新剂型,高性能助剂,制剂稳定性研究方法以及农药剂型加工专业和人才等方面对我国农药剂型加工行业的发展概况进行了简单综述,同时展望了未来农药剂型加工行业的发展前景。     

环糊精及其衍生物在农药领域应用的研究进展

环糊精及其衍生物具有 "内疏水、外亲水"的特殊分子结构,可与许多客体分子包结形成包合物。环糊精与农药形成包合物对农药分子具有增溶、控制释放、提高稳定性等功能,在农药制剂方面具有重要的应用价值。环糊精对农药污染物的降解有促进作用,对农药分子具有选择性识别作用,因而在农药污染物治理、农药残留检测方面也有重要的应用价值。综述了环糊精及其衍生物在作为农药剂型加工中的助剂、农药污染物治理和农药残留检测等方面应用的研究新进展,并对其在农药领域的发展趋势和应用前景进行了展望。     

农用飞防专用制剂的现状与发展

本文简要介绍了农用飞防农药制剂与常规制剂的区别,飞防药剂的筛选原则,飞防助剂的主要功效及飞防技术的今后发展等。作者认为,与农药飞防技术相匹配的农药专用制剂和助剂的研发、产品质量标准的制定、登记管理的政策法规及试验准则等将会成为今后的热点。农药飞防制剂和专用助剂的研发将以抗蒸发、抗漂移、沉淀渗透性好、润湿吸收快和安全广谱高效为主要方向,注重飞防药剂、剂型和复配制剂的筛选开发,同时借鉴美国、日本、韩国等已有的飞防农药制剂登记国家的经验,适合我国农药飞防作业的特色制剂和助剂将会得到快速的发展。     

4种助剂对3种水稻田常用除草剂减量增效作用

为明确助剂安融乐、激健、红太阳A8、Prime与水稻田常用除草剂二氯喹啉酸、2甲4氯钠、(口恶)嗪草酮协同使用的最佳增效剂量,评价筛选出具有最佳增效作用的助剂+除草剂协同组合,从而达到降低二氯喹啉酸、2甲4氯钠、(口恶)嗪草酮用量并提高其毒力的目的。采用整株生物测定法测定不同助剂与3种药剂混用后对稗(Echinochloa crusgalli)、鳢肠(Eclipta prostrata)的毒力及对籼稻、粳稻的安全性。结果表明,安融乐、激健、红太阳A8、Prime与50%二氯喹啉酸WP、56%2甲4氯钠SP、10%(口恶)嗪草酮SC协同使用的最佳剂量分别为180、225、120、320 mL/hm~2。4种助剂在最佳增效剂量下与3种药剂混用,均可显著降低二氯喹啉酸、(口恶)嗪草酮对稗以及2甲4氯钠对鳢肠的ED_(90),且对籼稻、粳稻幼苗生长均安全。筛选得到3个可降低除草剂用量且对水稻安全的助剂+除草剂协同增效组合,分别为50%二氯喹啉酸WP 220 g a.i./hm~2+红太阳A8 120 mL/hm~2,10%(口恶)嗪草酮SC 100 g a.i./hm~2+红太阳A8 120 mL/hm~2,56%2甲4氯钠SP 672 g a.i./hm~2+安融乐180 mL/hm~2。     

油酸甲酯助剂对除草剂增效作用及其对玉米苗期安全性测定

采用温室盆栽法测定了自制油酸甲酯助剂对3种玉米田常用除草剂磺草酮、莠去津和烟嘧磺隆药效的增强作用,并测定了该助剂分别与3种除草剂混用后对玉米苗期生长的影响。结果表明:油酸甲酯助剂对供试3种除草剂的药效均有显著增强作用,其中对磺草酮和莠去津药效的增强作用大于对烟嘧磺隆药效的增强作用,且除草剂低剂量使用时油酸甲酯助剂对其药效的增强作用比高剂量使用时更明显;油酸甲酯助剂分别与供试3种除草剂混用对玉米苗期生长有一定影响,以烟嘧磺隆抑制作用较强,莠去津次之。     

“七五”期间我国农药加工技术发展回顾

为了加速我国农药加工工业的发展,改变我国农药制剂品种少、质量差、助剂不配套、加工设备落后的状况。在“七五”期间,国家计委将农药新剂型新制剂开发列入科技攻关计划。其指导思想是通过攻关,使我国农药含剂质量,特别是可湿性粉剂和乳油的质量,达到或超过联合国粮农组织(FAO)规定的指标;增加新剂型和新制剂品种。要求开发50个农药新制剂和4种     

Adsorption-leaching study of the herbicides metamitron and chloridazon

Freundlich isotherms were obtained for the adsorption equilibrium of the herbicides metamitron and chloridazon with the components of a representative soil in a pesticide concentration range of 10-1000 γg ml^?1 for metamitron and 10-500 μg ml^?1 for chloridazon. The mobility of these herbicides through soil columns was also studied using the displacement technique described by Davidson (Soil Sci. Soc. Amer. Proc., 32 (1968) 629). The experiment was carried out simultaneously in three columns, two of which were fed with solutions of the herbicides while the third was used as a control. The herbicide solutions flowed down by gravity and were collected at the outlet at different times. The herbicide content of these outlet solutions was determined by Differential Pulse Polarography.     

除草剂对作物产生药害的原因及治理对策

本文论述了我国除草剂使用过程中作物产生药害的主要原因和除草剂药害的治理对策。提出:除草剂使用不合理,除草剂和作物本身的因素,异常的环境条件是药害产生的主要原因。杜绝假冒伪劣及不合格产品,加强除草剂试验、示范、推广工作,深化除草剂应用技术研究,加强农民用药技术水平培训是除草剂安全使用应解决的问题。     

Environmental fate of herbicides trifluralin, metazachlor, metamitron and sulcotrione compared with that of glyphosate, a substitute broad spectrum herbicide for different glyphosate-resistant crops

The introduction of crops resistant to the broad spectrum herbicide glyphosate, N-(phosphonomethyl)glycine, may constitute an answer to increased contamination of the environment by herbicides, since it should reduce the total amount of herbicide needed and the number of active ingredients. However, there are few published data comparing the fate of glyphosate in the environment, particularly in soil, with that of substitute herbicides. The objective of this study is to compare the fate of glyphosate in three soils with that of four herbicides frequently used on crops that might be glyphosate resistant: trifluralin, alpha,alpha,alpha-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine, and metazachlor, 2-chloro-N-(pyrazol-1-ylmethyl)acet-2',6'-xylidide for oilseed rape, metamitron, 4-amino-4,5-dihydro-3-methyl-6-phenyl-1,2,4-triazin-5-one for sugarbeet and sulcotrione, 2-(2-chloro-4-mesylbenzoyl)cyclohexane-1,3-dione for maize. The distribution of herbicides between the volatilized, mineralized, extractable and non-extractable fractions was studied, along with the formation of their metabolites in laboratory experiments using 14C-labelled herbicides, over a period of 140 days. The main dissipation pathways were mineralization for glyphosate and sulcotrione, volatilization for trifluralin and non-extractable residues formation for metazachlor and metamitron. The five herbicides had low persistence. Glyphosate had the shortest half-life, which varied with soil type, whereas trifluralin had the longest. The half-lives of metazachlor and sulcotrione were comparable, whereas that of metamitron was highly variable. Glyphosate, metazachlor and sulcotrione were degraded into persistent metabolites. Low amounts of trifluralin and metamitron metabolites were observed. At 140 days after herbicide applications, the amounts of glyphosate and its metabolite residues in soils were the lowest in two soils, but not in the third soil, a loamy sand with low pH. The environmental advantage in using glyphosate due to its rapid degradation is counterbalanced by accumulation of aminomethylphosphonic acid specifically in the context of extensive use of glyphosate.     

蔬菜安全生产过程中农药污染危害与控制途径分析

蔬菜产品从"田间到餐桌"需要经过一个较长的链条,其中蔬菜的生产在这个链条中占有重要地位。蔬菜安全生产是社会和谐发展的客观要求,是经济效益持续稳定的根本保障,生态健康也对蔬菜安全生产中农药的科学使用提出了更高要求。蔬菜生产过程中的污染包括产地环境污染和农业投入品污染,其中又以作为重要的农业投入品的农药引起的污染为主。农药是蔬菜安全生产中减少病虫草等危害损失、保障蔬菜产量的重要核心因素,但如果农药使用不科学就会污染环境、破坏生态平衡、造成蔬菜产品农药残留超标、作物药害或导致人们中毒,直接危害人类健康。国外为推行农产品质量安全从"田间到餐桌"全过程控制,随之相继出现了如良好农业规范(GAP)、良好生产规范(GMP)、危害分析和关键点控制体系(HACCP)等生产管理和控制体系。我国对农药污染控制技术手段比较薄弱,为缓解我国蔬菜生产、病虫害防治和农药污染之间的矛盾,必须对农药的使用进行全程调控。     

Characterization of Spatial Variability Structure in Three Separate Field Trials on Pesticide Dissipation

Experiments were carried out on three Italian farms to assess the degree of spatial variation of pesticide field concentration during treatment and during dissipation trials. Test pesticides were chloridazon and metamitron (both sugar-beet herbicides) applied as a tank mix. The classical statistical technique and geostatistics were used to summarize and evaluate variable spatial data. The results show that the actual values of pesticide concentration for application rate and initial concentration in all three areas are lower than expected, thus indicating that under field conditions only a part of the pesticide reaches the soil during the distribution. The actual values for both herbicides in all three areas expressed as percentage of expected values ranged from 44·1% to 64·2% for application rate and from 40·5% to 99·5% for initial concentration. The coefficient of variation was similar for both pesticides and ranged from 23·8 to 74·1 for application rate, 24·1 and 58·8 for initial concentration and 11·1 and 110·0 for dissipation half-lives. The high variability in application rate and initial concentration could be ascribed to an uneven herbicide distribution, and in dissipation studies to variation in half-lives for the rate of herbicide loss from soil in different parts of the field. Geostatistic analysis indicated little spatial correlation, probably because the sampling sites were widely spaced on the field. In all cases, the data were not sufficient to estimate the range of influence, probably because of the size of the experimental fields and the sampling strategy. © 1997 SCI.     

The influence of soil properties on the rates of degradation of metamitron,metazachlor and metribuzin

The rates of degradation of metamitron, metazachlor and metribuzin were measured in 12 mineral soils and the first order rate constants were compared with soil properties by regression analysis. Rates of metamitron degradation were best described by a multiple regression involving the silt content of the soil and the fraction of the total herbicide content which was available in the soil solution. Metazachlor degradation was best described by a multiple regression involving the sand content of the soil, the availability of the herbicide in the soil solution and soil microbial respiration. There was evidence that metribuzin degradation in any one soil was closely related to microbial activity, and rate constants per unit microbial respiration were derived for each soil. These rate constants were best described by a multiple regression involving the Freundlich adsorption constant and the sand content of the soils. The best regression equations for each herbicide were tested against observed degradation rates in an additional group of six soils. The calculated rates compared favourably with those observed for both metamitron and metazachlor, but with metribuzin, there was good agreement with one soil only.     

Fate of the herbicides glyphosate, glufosinate-ammonium, phenmedipham, ethofumesate and metamitron in two Finnish arable soils

The fate of five herbicides (glyphosate, glufosinate-ammonium, phenmedipham, ethofumesate and metamitron) was studied in two Finnish sugar beet fields for 26 months. Soil types were sandy loam and clay. Two different herbicide-tolerant sugar beet cultivars and three different herbicide application schedules were used. Meteorological data were collected throughout the study and soil properties were thoroughly analysed. An extensive data set of herbicide residue concentrations in soil was collected. Five different soil depths were sampled. The study was carried out using common Finnish agricultural practices and represents typical sugar beet cultivation conditions in Finland. The overall observed order of persistence was ethofumesate > glyphosate > phenmedipham > metamitron > glufosinate-ammonium. Only ethofumesate and glyphosate persisted until the subsequent spring. Seasonal variation in herbicide dissipation was very high and dissipation ceased almost completely during winter. During the 2 year experiment no indication of potential groundwater pollution risk was obtained, but herbicides may cause surface water pollution.     

农药乳油中有害有机溶剂替代的研究进展

农药乳油中含有苯、甲苯、二甲苯等有害有机溶剂，这些溶剂闪点低、易挥发、毒性高，对生态环境和人类健康具有潜在风险。本文主要综述了农药乳油中有机溶剂的使用现状、危害及可能的解决措施，重点介绍了以生物源溶剂、矿物源溶剂、人工合成溶剂替代乳油中有害有机溶剂的研究进展。这些替代溶剂低毒、环保，在乳油中具有很好的应用前景，但通过实验筛选替代溶剂通常费时费力，而热力学模型COSMO-RS可以从理论上预测替代溶剂对农药的溶解性，再通过实验加以验证，省时省力，可加快乳油中替代溶剂的筛选，对开发环境友好型乳油具有指导意义。     

Differential sensitivity of Atriplex patula and Chenopodium album to sugar beet herbicides: a possible cause for the upsurge of A. patula in sugar beet fields

In the last decade, the prevalence of Atriplex patula as a weed in the Belgian sugar beet area has increased. Possible reasons for its expansion in sugar beet fields, besides a poor implementation of the low‐dose phenmedipham/activator/soil‐acting herbicide (FAR) system, might be low sensitivity or evolved resistance to one or more herbicides used in sugar beet. Dose – response pot bioassays were conducted in the glasshouse to evaluate the effectiveness of five foliar‐applied sugar beet herbicides (metamitron, phenmedipham, desmedipham, ethofumesate and triallate) and three pre‐plant‐incorporated herbicides (metamitron, lenacil, dimethenamid‐P) for controlling five Belgian A. patula populations. Local metamitron‐susceptible and metamitron‐resistant populations of Chenopodium album were used as reference populations. Effective dosages and resistance indices were calculated. DNA sequence analysis of the photosystem II psbA gene was performed on putative resistant A. patula populations. Overall, A. patula exhibited large intraspecific variation in herbicide sensitivity. In general, A. patula populations were less susceptible to phenmedipham, desmedipham, ethofumesate and triallate relative to C. album populations. Two A. patula populations bear the leucine‐218 to valine mutation on the chloroplast psbA gene conferring low level to high level cross‐resistance to the photosystem II inhibitors phenmedipham, desmedipham, metamitron and lenacil. In order to avoid insufficient A. patula control and further spread, seedlings should preferentially be treated with FAR mixtures containing higher‐than‐standard doses of metamitron and phenmedipham/desmedipham and no later than the cotyledon stage.     

杀线虫苏云金芽胞杆菌NBIN-863高含量悬浮剂的研制

目前我国微生物农药原药生产技术已达到甚至超过发达国家水平,但制剂技术却存在较大差距,主要体现在剂型结构不合理、制剂质量差、农药助剂种类及品种少、剂型加工工艺总体水平还比较落后等方面。苏云金芽胞杆菌（Bt）等功能微生物产品的市场容量及应用效果与剂型是密切相关的。为了明确新型生物杀线剂NBIN-863的最佳施用剂型,特开展此试验。通过对防腐剂、分散剂、悬浮剂等不同助剂的选择,研制了一种高含量Bt悬浮剂（5.2×10⁹～7.9×10⁹CFU/mL）。配方优化试验表明,在Bt发酵液中加入0.4%防腐剂山梨酸钾、1.0%分散剂硅酸镁铝、4.0%悬浮剂木质素磺酸钙,用盐酸调节pH至4.5,54℃热储前芽胞数最高为7.9×10⁹ CFU/mL,对秀丽隐杆线虫活性最高,LC₅₀为2.83 mg/L,对黄瓜根结线虫田间防效达68.64%。综合各指标,尤其是对秀丽隐杆线虫的半致死浓度,杀线虫NBIN-863悬浮剂（7.9×10⁹ CFU/mL）效果最好,不仅流动性好,而且耐贮藏,是防治作物根结线虫病的理想药剂。